import Vue from 'vue'
import VueRouter from 'vue-router'
import Login from '../components/Login.vue'
import Home from '../components/Home.vue'
import Welcome from '../components/Welcome.vue'
import Users from '../components/user/Users.vue'

Vue.use(VueRouter)

const routes = [
  { path: '/', redirect: '/login' },
  { path: '/login', component: Login },
  {
    path: '/home',
    component: Home,
    redirect: '/welcome',
    children: [
      {
        path: '/welcome',
        component: Welcome
      },
      {
        path: '/users',
        component: Users
      }
    ]
  }
]

const router = new VueRouter({
  routes
})

/**
 * 路由导航
 * to：将要访问的路径
 * from：代表从哪个路径跳转而来
 * next：是一个函数，表示放行
 * next()放行，next("/login")强制跳转
 */
router.beforeEach((to, from, next) => {
  // 如果访问登录页面====放行
  if (to.path === '/login') {
    return next()
  }
  // 获取token
  const tokenStr = window.sessionStorage.getItem('token')
  if (!tokenStr) {
    return next('/login')
  }
  return next()
})

export default router
